Amongst various dispensers for applying medicament, a typical medicament container includes a flexible vial storage portion and a nozzle for dispensing medicament by squeezing the vial between its side walls. Another type of medicament dispenser is an accordion-like or piston-like pump dispenser which is actuated by squeezing the vial between a bottom wall and the nozzle so as to compress the vial in its longitudinal direction, rather than from its sides. An example of the piston-like dispenser which ejects precalibrated dosage of medicament is described in detail in U.S. Pat. No. 5,613,957, which is expressly incorporated herein by reference.
In recent years, pump-type dispensers have received attention for their use in accurately dispensing small doses of medicaments, e.g., for nasal applications. One persistent problem associated with pump-type dispensers for dispensing medicaments is preventing contamination of the medicament which can occur when the medicament that has been exposed to ambient air returns and/or remains in the outlet channel, e.g., within the nozzle. One solution to this problem is to simply add preservatives to the medicament being dispensed, thereby preventing bacterial growth. However, this solution has obvious disadvantages, e.g., added costs and toxicity of the preservatives. In order to prevent bacterial growth in medicament which does not contain preservatives while allowing dispensation of multiple doses of the medicament, the nozzle must prevent any medicament that has been previously exposed to ambient air from being reintroduced, or "sucked back," into the outlet channel of the nozzle, i.e., prevent any "dead volume." "Dead volume" is defined herein as the volume of space within the outlet channel of the pump where medicament can come into contact with the open air and remain. If any residual medicament remains within the dead volume, this residue could serve as a host environment for germ growth.
Another consideration involved in designing pump-type dispensers for medicaments is ensuring accurate dispensation of a predetermined quantity of medicament, e.g., ranging from 5 .mu.l to greater volumes, upon each actuation of the dispenser, irrespective of the orientation of the dispenser or the force applied by the user to the actuation mechanism of the dispenser. While many pump-type dispensers provide an upper limit of the quantity of medicament dispensed upon each actuation of the dispenser, these pumps often dispense varying quantities of medicament as a function of the speed and/or force of actuation of the actuation mechanism of the dispenser. In the case of a pump-type dispenser which generates aerosol or spray-type discharges, not only will the dispensed dose of medicament vary with the speed and/or the force of actuation of the actuation mechanism, but the spray pattern, or the plume, of the dispensed medicament will also vary with the speed and/or the force of actuation.
It should also be noted that persons who suffer from asthmatic or allergic condition routinely need to carry a medicament dispenser with them for emergency situations, but both the existing pressurized medicament dispensers and non-pressurized dispensers have significant drawbacks. The pressurized dispensers are not always ready for use unless they incorporate a heavy glass bottle sustaining vacuum. The non-pressurized devices generally require a particular orientation for dispensing medicament, as well as suffering from a measurable dead volume in the nozzle area.
Yet another problem in designing pump-type dispensers for medicaments is ensuring the ease of applying the medicament. Conventional pump-type dispensers for nasal application, an example of which is shown in FIG. 2, are generally actuated by compression along the length of the dispenser. As shown in FIG. 2, the conventional nasal pump 200 is actuated by pushing down on the syringe arms 203 while supporting the bottom portion 202 with the thumb. The combined actuation motion leads to difficulty in holding the nasal pump in stationary position, and usually results in removal of the nozzle tip 204 from the nostril area. For those users who may have greater than average difficulty with the actuation motion, e.g., elderly patients with arthritis or young children, accidental application of the nasal medicament to the face or into the eye may occur.
Yet another problem associated with the pump-type medicament dispensers is manufacturing complexity: pump-type medicament dispensers are currently made of numerous parts and are highly delicate to assemble. As the number of components increases, the difficulty and cost of mass production increases correspondingly. For example, many of the pump-type dispensers incorporate springs, which pose problems in the manufacturing process because of the springs' tendency to get intermingled. In addition, very small size of the gaskets and other components make relative movement of the parts difficult. Furthermore, increased number of components also increases the complexity of achieving stability and compatibility of the component materials with the medicament.
One attempt to solve the above-described problems associated with applying medicament from a dispenser is described in my U.S. Pat. No. 5,267,986, which discloses a system including a cartridge for actuating a piston-like or accordion-like vial-dispenser for applying medicament to an eye. The cartridge disclosed in U.S. Pat. No. 5,267,986 includes: a housing for holding the vial-dispenser, a telescoping cylinder for compressing the vial-dispenser in the longitudinal direction to load the vial with medicament; a locking mechanism for locking the telescoping cylinder and the vial-dispenser in the loaded position, against the urging of a spring mechanism of the vial-dispenser; and a trigger mechanism for releasing the telescoping cylinder and the vial-dispenser from the locked position to release the medicament loaded in the dispenser by means of the force of the spring mechanism. In order to obviate the need for a discrete spring element in the pump mechanism of the vial-dispenser, a portion of the vial-dispenser body is made of an elastic material which is compressible and provides spring force. The two-step process in which the cartridge disclosed in U.S. Pat. No. 5,267,986 loads and subsequently releases the medicament from a vial-dispenser defines the basic operation a "reverse pump," an example of which is described in U.S. Pat. No. 5,613,957.
The dispensing system disclosed in U.S. Pat. No. 5,267,986 addresses some of the previously-mentioned problems by enabling a user to apply a predetermined dose of medicament independent of the physical force, or speed, applied to the dispensing system by the user: the releasing force or speed of the dispensed medicament is dependent on the integral spring element of the dispensing system. Whereas conventional pump-type dispensers often utilize compression along the longitudinal axis for release of medicament, the actuation motion of the release mechanism described in U.S. Pat. No. 5,267,986 is preferably achieved in a direction perpendicular to the longitudinal axis of the vial-dispenser to ensure enhanced leverage for the user.
While the dispensing system disclosed in U.S. Pat. No. 5,267,986 addresses some of the previously-mentioned problems, at least one significant problem remains: because elastic materials, particularly elastomeric materials and springs, tend to exhibit hysteresis, spring force decreases if the spring mechanism is kept in the compressed position, i.e., in the loaded, locked position. Although the deformation of spring is generally reversible if the spring is returned to, and maintained in, the unbiased state for some period, some of the deformation becomes irreversible, or experiences "creep," if the spring is kept in the compressed state beyond a certain threshold period of time, which threshold period varies with the spring material. The amount of loss of spring force is dependent on the tendency of a particular spring material to "creep," and it is known that metal springs tend to exhibit much less "creep" than plastic springs. The hysteresis of elastic materials used to form the spring mechanism of the pump described in U.S. Pat. No. 5,613,957 is due to loss of some of the spring property when the spring element remains in the compressed state for an extended, and often unexpected, period of time.
Two examples illustrate the practical implications of the above-mentioned hysteresis problem in connection with the dispensing system disclosed in U.S. Pat. No. 5,267,986. As a first example, a user places the dispensing system in the loaded state but does not actuate the release mechanism for several hours due to an interruption. When the release mechanism is finally actuated, hysteresis of the spring mechanism causes the dosage of released medicament to vary from the dosage calibrated to be released under normal conditions. As a second example, a user places the dispensing system in the loaded state but subsequently forgets about the loaded system; the user does not actuate the release mechanism for several weeks or months. In this situation, not only will the initially-released dosage vary from the calibrated dosage, due to lower actuation speed or force, but subsequently-dispensed dosages will also vary from the calibrated dosage due to a type of permanent deformation, or "creep," that has occurred, i.e., a permanent change in the actuation stroke. In view of the above-described problem of spring deformation, it would be desirable to have a pump-type medicament-dispensing system which allows the user, by means of a single actuation motion, to load the vial with medicament and subsequently dispense the medicament, without any intervening locking step.
Pump-type dispensers for applying nasal medicaments are faced with yet another problem in providing the users with some level of discreetness: the sight of a conventional pump-type nasal dispenser positioned inside of a nostril is unseemly and often causes embarrassment for the user. Accordingly, it would be desirable to achieve dispensation of nasal medicament without presenting the unsightly appearance of the dispenser positioned inside the nostril.
Still another problem faced by pump-type dispensers is achieving a tight seal of the dispenser after filling it with liquid. The standard approach is to utilize plugs or lids which are formed to mechanically engage the filling opening of a pouch or a container. The main difficulty with this approach is that the allowable mechanical tolerances of the interacting parts of the plug or lid and the opening of the pouch or the container must be extremely small in order to achieve a tight, substantially hermetic seal. Furthermore, even if the interacting parts initially form a tight seal, the portions of the interacting parts which are under pressure tend to experience a "creep," i.e., deformation of the material, over time. Accordingly, the "creep" phenomenon tends to reduce the tightness of the seal. Thus, there is a need for a mechanical closure system which achieves and maintains a hermetic seal of a pouch or a container over the life of the container.
Accordingly, it is an object of the present invention to provide a pump-type dispenser for dispensing medicament in droplets or spray form, which dispenser facilitates easy application of the medicament while ensuring positional stability of the dispenser during the actuation motion.
It is another object of the present invention to provide a pump-type dispenser for applying medicaments into the nasal passage, which dispenser provides the user with a nasal screen for discreetness.
It is yet another object of the present invention to provide a pump-type dispenser for applying medicaments into the nasal passage, which dispenser provides a guide for aligning the dispenser nozzle with the nasal passage.
It is yet another object of the present invention to provide a pump-type dispenser for applying medicament into the nasal passage, which dispenser ensures a one-way movement of medicament through the nozzle of the dispenser.
It is yet another object of the present invention to provide a pump-type dispenser which has a substantially zero "dead volume" in the nozzle portion so that no medicament which has been exposed to ambient air can remain, i.e., the medicament is completely released once it passes through the outlet nozzle, or the combined effect of the surface tensions of the medicament and the surrounding outlet nozzle forces any remaining medicament out of, and away from, the outlet portion.
It is yet another object of the present invention to provide a pump-type dispenser for dispensing nasal medicament, which dispenser minimizes the number of parts for manufacturing.
It is yet another object of the present invention to provide a pump-type dispenser for nasal medicament, which dispenser incorporates a nozzle adapted to generate an aerosol-type discharge by means of elastic, radial deformation along the circumference of the nozzle which simultaneously functions as an integral spring and an elastic valve, while substantially maintaining the physical profile in the direction of the longitudinal axis of the nozzle.
It is yet another object of the present invention to provide a pump-type dispenser for nasal medicaments, which dispenser does not require propellants such as CFCs, the release of which is harmful to the ozone layer, or the release pressure of which propellant is temperature dependent, thereby creating variations in dispensed dosages.
It is yet another object of the present invention to provide a pump-type dispenser for nasal medicaments, which dispenser emits a predetermined dose of medicament upon each actuation of the dispenser, irrespective of the orientation of the dispenser and the force applied by the user to actuation mechanism.
It is yet another object of the present invention to provide a pump-type dispenser for nasal medicaments, which dispenser emits a predetermined dose of medicament upon each actuation of the dispenser, irrespective of the force applied by the user to the actuation mechanism of the dispenser.
It is a further object of the invention to provide a nasal-medicament dispensing system which can accurately deliver a small, calibrated amount of medicament by means of a single actuation motion which loads the system with medicament and subsequently dispenses the loaded medicament immediately thereafter without any intervening locking step.
It is a further object of the invention to provide a nasal-medicament dispensing system having a single actuation motion for loading and dispensing the medicament, which system incorporates an elastomeric spring element as an integral portion of the body of the dispensing system.
It is a further object of the invention to provide a nasal-medicament dispensing system which includes an actuation mechanism for actuating a vial-dispenser of the type having a spring configuration, e.g., an accordion-like or piston-like vial-dispenser, which actuation mechanism requires minimal force for actuation.
It is a further object of the invention to provide a nasal-medicament dispensing system which substantially eliminates any possibility that spring elements of the dispensing system will exhibit hysteresis of spring characteristics.
It is a further object of the invention to provide a nasal-medicament system in which the actuation motion of the actuation mechanism for dispensing the loaded medicament is in the direction perpendicular to the longitudinal axis of the vial dispenser to ensure enhanced leverage for the user and to avoid the actuation motion being parallel to the compression axis of the spring element.
It is a further object of the invention to provide a method of accurately delivering a small, calibrated amount of medicament by means of a single actuation motion of a medicament-dispensing system which loads the system with medicament and immediately dispenses the loaded medicament thereafter without any intervening locking step.
It is a further object of the invention to provide a method of dispensing a small, calibrated amount of medicament by means of an actuation mechanism for actuating an accordion-like or piston-like vial-dispenser, which actuation motion requires minimal force for actuation.
It is another object of the present invention to provide a mechanical closure system for achieving a tight, substantially hermetic seal of a pouch or a container having an opening.
It is another object of the present invention to provide a method of mechanically sealing a pouch or a container having an opening to achieve a tight, substantially hermetic seal while simultaneously allowing delivery of gels or suspensions via an outlet nozzle.
It is yet another object of the present invention to provide a mechanical closure system for a pouch or a container having an opening, which mechanical closure system compensates for deformation of the interacting parts of the mechanical closure system and the pouch or the container.
It is yet another object of the present invention to provide a mechanical closure system for achieving a tight, substantially hermetic seal of a pouch or a container having an opening, which system does not require extremely small tolerances for the interacting parts.
It is yet another object of the present invention to provide a method of mechanically sealing an opening of a pouch or a container after having introduced liquid into the container through the opening, which method eliminates the need to provide vacuum conditions for filling the container and, thereby, substantially reduces the cost of the mechanical system for filling the container.
It is yet another object of the present invention to provide a method of mechanically sealing an opening of a pouch or a container, which method involves removably sealing the opening of the pouch or the container in a first configuration, and permanently sealing the opening of the pouch or the container in a second configuration.
It is yet another object of the present invention to provide a system of mechanically sealing an opening of a pouch or a container, which system provides a single-piece sealing element consisting of a mechanical plug detachably coupled to a crimping element via a flange for removably sealing the opening of the pouch or the container, and the system further providing that the crimping element may be detached from the mechanical plug to permanently seal the opening of the pouch or the container.
It is yet another object of the present invention to provide a spray-type dispensing system having a swirling chamber in the region of the nozzle for generating a spray pattern, which system substantially minimizes the head loss in the swirling chamber and in the outflow channels surrounding the swirling chamber.
It is yet another object of the present invention to provide method of generating a spray-type emission from a medicament dispensing system having a swirling chamber in the region of the nozzle for generating a spray pattern, which method substantially minimizes the head loss in the swirling chamber and in the outflow channels surrounding the swirling chamber.